Notice that the amount of 58Ni increased by 1% and the amount of 60Ni increased by 0.8%. In total this equals the 1.8% decrease in the amount of 64Ni.
Harry On Tue, Mar 29, 2016 at 11:49 PM, Eric Walker <[email protected]> wrote: > On Tue, Mar 29, 2016 at 5:07 PM, Bob Higgins <[email protected]> > wrote: > >> First of all, it is reasonable to presume that any Zn contamination would >> have a natural isotopic ratio. The natural abundance for 64Ni is 0.9%. So, >> for the reported 4.4% of m=64 to be 64Zn + natural 64Ni, there would have to >> be a 64Zn contamination of about 3.5 atom%. 64Zn is about 50% natural >> isotopic ratio for Zn, so there would have to be about 7 atom% concentration >> of Zn in the Ni powder for this to be the answer for the measured >> concentration at m=64. This would be a huge contamination. > > > Just to play devil's advocate, the contamination would not need to have been > in the pure nickel powder. It could have come from another source, and > somehow gotten into the fuel mixture. The 7 atom% concentration would thus > be for the composite fuel mixture. (I will have to trust your calculation! > My number for both zinc isotopes together was ~ 3.5 atom%.) The composite > fuel mixture appears to have been what was measured in the laser-atomic > emission spectrometry assay [1]. > >> Also, Parkhomov's jar of Ni powder claimed it to be 99.9% Ni. Even if all >> of the 0.1% were Zn, that would only mean 0.05atom% of 64Zn to contaminate >> the 64Ni measurement. That would be consistent with the non-measurement of >> Zn in the EDS and the low value for Zn atomic percent reported by laser >> atomic emission spectroscopy in the same Sochi presentation. > > > Perhaps you are referring to an EDS assay that was reported elsewhere and > not in the slides. The one in the slides (SEM-EDS) was of Rossi's reactor. > >> ICP-MS is a bulk measurement. 1-2 mg of Ni powder would be dissolved in >> acid, diluted, and then introduced into the ionization chamber. So the 7% >> concentration of Zn could not be just a tiny spot on a particle, it would >> have to be 7% of the entire sample mass digested in the acid. When MFMP >> tested the powder it received from Parknomov (ICP-MS), it was found to have >> the normal, natural concentration of 64Ni. > > > For the ICP-MS assay in the slides, I take it the fuel and ash will have > been dissolved, and that the composite powder, a prominent part of which was > nickel, but not by any means all nickel, will have been analyzed. Or are > you explaining that it was the pure nickel powder from the jar whose label > was shown earlier in the thread that was analyzed in the ICP-MS? If it was > the fuel and not the pure nickel from the jar that was analyzed in the > ICP-MS assay, it is easy to imagine there having been zinc impurity present. > > According to the slides, the ICP-MS assay was done by the Vernadsky > Institute. I take it there was a second ICP-MS assay done by MFMP? Or are > the two the same? > >> The 64Ni concentration is inconsistent with the explanation of Zn >> contamination. I have asked Bob Greenyer to review this with Parkhomov and >> arrive at a less flip answer. >> >> For now, we simply cannot trust the m=64 data in his Sochi ICP-MS report - >> neither the fuel or the ash - until a better explanation of the anomalous >> values is supplied. > > > Yes -- I have no idea what's going on. Perhaps there's a simple > explanation. Little makes sense to me at the moment. > > Eric > > > [1] > https://drive.google.com/file/d/0B5Pc25a4cOM2cHBha0RLbUo5ZVU/view?pref=2&pli=1 >
